Java生成安全證書

Question

java中如何生成此命令的模擬輸出？

openssl req -x509 -nodes -days 365 -newkey rsa:4096 -keyout server.key -out cert.pem 

我接下來做

KeyPairGenerator gen = KeyPairGenerator.getInstance(keyAlgo); 
SecureRandom random = new SecureRandom(); 
gen.initialize(keyLength, random); 
keyPair = gen.genKeyPair(); 
PublicKey pubk = keyPair.getPublic(); 
PrivateKey prvk = keyPair.getPrivate(); 

但結果我收到另一長度公鑰和私鑰。

Answer 1

下面是一個例子：

Date validityBeginDate = new Date(System.currentTimeMillis()); 
Date validityEndDate = new Date(System.currentTimeMillis() + 365 * 24 * 60 * 60 * 1000); //1 year from now 

KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA", "BC"); 
keyPairGenerator.initialize(4096, new SecureRandom()); 

KeyPair keyPair = keyPairGenerator.generateKeyPair(); 

X509V1CertificateGenerator certGen = new X509V1CertificateGenerator(); 
X500Principal dnName = new X500Principal("CN=John Doe"); 

certGen.setSerialNumber(BigInteger.valueOf(System.currentTimeMillis())); 
certGen.setSubjectDN(dnName); 
certGen.setIssuerDN(dnName); 
certGen.setNotBefore(validityBeginDate); 
certGen.setNotAfter(validityEndDate); 
certGen.setPublicKey(keyPair.getPublic()); 
certGen.setSignatureAlgorithm("SHA256WithRSAEncryption"); 

X509Certificate cert = certGen.generate(keyPair.getPrivate(), "BC"); 

使用PEMWriter輸出你的PEM文件。